Poor Multi Target Tracking Fidelity with Positional Tracking

We are running into an issue where we are upgrading our project, and vuforia now lists Rotational tracking as deprecated and urges us to use Positional tracking. Tracking fidelity when using Positional tracking is noticeably much worse than Rotational tracking. Switching back to Rotational fixes the issue however there are other reasons we would like to switch to using Positional tracking. We have gone through the "Optimizing your image target" steps, however since this same image target was working previously, and is only now experiencing issues in the new tracking mode we suspect something to do with that configuration is to blame. We are in Unity 2018.4 and would like to avoid upgrading to 2019 if we don't have to. We are currently using Vuforia 8.3.8. Our application targets both ios and android. I'll include a screenshot of our current vuforia configuration settings, perhaps there is something obvious there we have configured incorrectly.